Re: crashes with Fibers

[Amirouche Boubekki <amirouche@hypermove.net>]

On 2018-07-02 00:32, Amirouche Boubekki wrote:
> On 2018-07-01 15:09, Clément Lassieur wrote:
>> Amirouche Boubekki <amirouche@hypermove.net> writes:
>> 
>>> Sorry, I did not read the code. What are you trying to achieve?
>> 
>> Within a fiber, I need to spawn several Guile-Git clones in parallel.
>> Since they block the Fibers scheduler, they need to be in separate
>> threads.
> 
> I tried that in the past it was working, but don't remember correctly
> how I did.

> epoll is dead seems to indicate that there is no fiber scheduler 
> running
> from the thread your are calling put-message. This might be a design 
> decision
> or not. My understanding is that your code should work as intended.

You test5 code should definitly work. Otherwise, it requires to 
pre-allocate
as many thread as you need before you know you will them. May be we can 
look
at it backward and say, that allocating a pool of threads in advance is 
more
interesting performance wise.

> Anyway, try to spawn the thread and/or create the channel before you
> run fibers. I can't try that myself because of my slow connection which
> takes ages to install guile-fibers.
> 
> Something like:

(use-modules (fibers))
(use-modules (fibers channels))

> (define (test6)
>   (let ((channel (make-channel)))
>     (call-with-new-thread
>      (lambda ()
>        (put-message channel "hello world")))
>     (run-fibers
>      (lambda ()
>        (spawn-fiber
>         (lambda ()
>           (format #t "~a~%" (get-message channel)))))
>     #:drain? #t)))

It works on my side.